From the Guidelines
The initial dose of atomoxetine (Strattera) is 0.5 mg/kg once daily for children and adolescents weighing less than 70 kg, and 40 mg once daily for adults and children weighing more than 70 kg. This dosage is based on the most recent evidence from the study published in 2022 1. The medication should be taken in the morning or evening, consistently at the same time each day, and can be taken with or without food. Some key points to consider when prescribing atomoxetine include:
- The dose can be increased to the target dose after 3 days at the initial dose, with a maximum recommended dosage of 1.4 mg/kg/day or 100 mg/day, whichever is lower 1.
- The dose should be increased gradually to minimize side effects such as nausea, decreased appetite, fatigue, and initial blood pressure changes.
- Full therapeutic effects may take 2-4 weeks to develop.
- Atomoxetine works by inhibiting norepinephrine reuptake in the brain, which helps improve attention and reduce impulsivity in ADHD without the stimulant properties of medications like methylphenidate or amphetamines 1. It is essential to monitor patients closely for suicidality, clinical worsening, and unusual changes of behavior, especially during the first few months of treatment or at times of dose change, as analyses of twelve placebo-controlled trials in children and adolescents showed a greater risk of suicidal ideation during treatment in those participants receiving atomoxetine 1.
From the FDA Drug Label
Dosing of children and adolescents up to 70 kg body weight - Atomoxetine capsules should be initiated at a total daily dose of approximately 0.5 mg/kg Dosing of children and adolescents over 70 kg body weight and adults - Atomoxetine capsules should be initiated at a total daily dose of 40 mg
The initial dose of atomoxetine (Strattera) is 0.5 mg/kg for children and adolescents up to 70 kg body weight and 40 mg for children and adolescents over 70 kg body weight and adults 2.
From the Research
Initial Dose of Atomoxetine
The initial dose of atomoxetine (Strattera) is not explicitly stated in the provided studies as a specific value for all patients. However, the dosing is described as weight-based.
Weight-Based Dosing
- For children and adolescents weighing 70 kg or less, the target dosage is 1.2 mg/kg/day 3.
- For children and adolescents weighing over 70 kg and adults, the recommended dosage is 80 mg/day 3.
- A study also mentions that a dose of approximately 1.2 mg/kg per day is required to attain a maximal symptom response in acute studies 4.
- Another study mentions a transition from methylphenidate or amphetamine to atomoxetine, starting with 0.5 mg/kg/day atomoxetine plus full-dose psychostimulant for 1 week, followed by 1.2 mg/kg/day atomoxetine plus half-dose psychostimulant in the second week 5.